Rv2022c Family assigned · medium auto-curated

H37Rv Rv2022c · MTBC0 mtbc0_002152 · 201 aa · 2290732–2291337 (-) · RefSeq NP_216538.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationtype II toxin-antitoxin system RelE/ParE family toxin
Revised (this work)Type II toxin-antitoxin system RelE/ParE family toxin. Pfam: Gp49 (PF05973.21).

Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.

Curated reference (UniProt)

UniProt O53468 SwissProt · reviewed · Evidence at protein level
UniProt namePutative toxin HigB2
Curated functionPutative toxic component of a type II toxin-antitoxin (TA) system. Its cognate antitoxin would be HigA2.

UniProt still lists this protein as Putative toxin HigB2; the revised annotation above is ahead of the current UniProt record.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionPhage derived protein Gp49-like (DUF891)
Orthologous groupCOG4683

Orthology-based transfer (eggNOG 5.0.2, diamond). EC/KO/GO/CAZy are computed annotations, not manual curation; cross-check against the primary literature before treating a specific reaction as established.

Conservation & selection (intra-MTBC, 145 209 strains)

pN/pS 0.852 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 4 synonymous, 11 missense, 0 nonsense, 0 frameshift

pN/pS from segregating SNPs (singletons removed) normalised by possible sites. Low pN/pS = purifying selection (a strong signal that a "hypothetical" is a real, constrained gene). A high pN/pS is ambiguous: relaxed constraint or positive selection (drug resistance, antigenic variation) inflate it; e.g. rpoB/katG/pncA score high here for resistance, not loss of function. A clonal disruption (one allele over a clade) suggests lineage pseudogenisation; a convergent one (many independent alleles) is typical of resistance loss-of-function.

Domains (Pfam, hmmscan --cut_ga)

PfamAccessioni-EvalueResiduesDescription
Gp49PF05973.21 1.2e-2087–181 Phage derived protein Gp49-like (DUF891)

Functional interaction network (STRING v12, guilt-by-association)

Closest characterised functional partner: higA2 (transcriptional regulator), high confidence from genomic context alone (score 981 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv2021c higA2 transcriptional regulator 998 981 ctx neighborhood:786 fusion:648 cooccurence:771 textmining:912
Rv3183 higA3 transcriptional regulator 927 800 ctx cooccurence:773 textmining:651
Rv2023c hyp hypothetical protein 713 713 ctx neighborhood:711
Rv2020c Rv2020c, (MTV018.07c), len: 99 aa. Conserved hypothetical protein, nearly identical to C-terminal part of hypothetical protein RvD1-Rv2024c' 565 564 ctx neighborhood:558
Rv1956 higA antitoxin HigA 784 252 textmining:724
Rv3384c vapC46 ribonuclease VapC46 673 177 textmining:620
Rv3750c vapB50 excisionase 607 170 textmining:547
Rv2866 relG toxin RelG 454 169
Rv2865 relF antitoxin RelF 510 167 textmining:436
Rv0918 hyp hypothetical protein 504 160 textmining:434
Rv3749c vapC50 hyp hypothetical protein 693 157 textmining:651
Rv0065 vapC1 ribonuclease VapC1 501 153 textmining:436
Rv0268c hyp hypothetical protein 541 59 textmining:533
Rv3188 hyp hypothetical protein 445 55 textmining:437
Rv1955 higB toxin HigB 809 52 textmining:807

STRING combines evidence channels (neighborhood, fusion, cooccurrence, coexpression, experimental, database, text-mining) into a 0–1000 score. The ctx badge marks edges carried by the genomic-context channels (conserved neighborhood, fusion, phylogenetic co-occurrence), which are independent of orthology and structure and the strongest signal for an unknown gene. The no text-mining column recomputes the score from data alone, so a link that does not depend on the literature is visible. Association is a function hypothesis, not proof: corroborate with the operon context and the primary literature before assigning a function.

Evidence

  • Legacy H37Rv annotation: hypothetical protein
  • MTBC0 PGAP product: type II toxin-antitoxin system RelE/ParE family toxin
  • Pfam (hmmscan --cut_ga): Gp49 PF05973.21 (E=1e-20)
  • (auto-curated by rules from PGAP + Pfam + Foldseek; not hand-reviewed)

Sources

  • Ancestral sequence & coordinates: Harrison LB et al. (2024), An imputed ancestral reference genome for the MTBC, doi:10.1101/2023.09.07.556366
  • Product annotation: NCBI PGAP on MTBC0; legacy from H37Rv NC_000962.3 (RefSeq NP_216538.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Gp49 (PF05973.21)
  • Sequence-level signal: ESM Atlas (EvolutionaryScale × BioHub) — exploratory
  • Controlled vocabulary: eggNOG-mapper 2.1.12 (Cantalapiedra et al. 2021, doi:10.1093/molbev/msab293), eggNOG 5.0 DB (Huerta-Cepas et al. 2019) — OG COG4683
  • Curated reference: UniProt O53468 (SwissProt, reviewed; Evidence at protein level)
  • Intra-MTBC selection: pN/pS and disruption from SPDI variants of 145 209 MTBC strains (this work, local collection vs H37Rv NC_000962.3)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 27 functional partner(s); context anchor higA2
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002152|Rv2022c|
MNVPWENAHGGALYCLIRGDEFSAWHRLLFQRPGCAESVLACRHFLDGSPVARCSYPEEYHPCVISRIALLCDSVGWTADVERISAWLNGLDRETYELVFAAIEVLEEEGPALGCPLVDTVRGSRHKNMKELRPGSQGRSEVRILFAFDPARQAIMLAAGNKAGRWTQWYDEKIKAADEMFAEHLAQFEDTKPKRRKRKKG